Blenderella, why is this step done?


There is a step in chapter 2-1-eyeball, (minute 8:57), that is very simple to follow, but there is no explanation of why we should take that step.
chapter 2-1-eyeball, minute 8:57: “under modifiers, increase the subdivisions view to 2.”
Could someone explain what this step does and how it can help the modeling?

the subsurf modifier creates a additional mesh between the vertices that already create your object. if you use ‘catmull-clark’ this additional mesh is smoothed. the ‘view’ count tells blender how many times your polygons are subdivided in the 3dview window into four additional polygons. the ‘render’ count does the same for the render view. you increase the ‘view’ count to make the sphere more round and detailed. maybe you don’t see much of it, depending on your screen resolution. if you want to see this effect: add a cube, add a ‘subdivision surface’ modifier to this cube and change the view count from 0 to 1 to 2.

i thought this over, because i have to admit that a level 2 subsurf seems to be very high poly for the eyes (which already had no low polycount before subdividing). a reason could be, that the eyelids need to be placed perfectly on top of the eyes. therefor a very detailed eye gives the best guidelines. however i don’t think this step is necessary.

Thanks mikksu
The Blenderella DVD is a great tutorial asset. However, I think the author could make another tutorial DVD for beginners like me, explaining why some of the steps were taken (if steps were necessary, or advisory), etc. Kind of like behind the scene extras in commercial movie dvds.

@mikksu: “you increase the ‘view’ count to make the sphere more round and detailed”

I thought when we subdivided the sphere became more round and detailed.
Doesn’t this step :“under modifiers, increase the subdivisions view to 2.” have only direct relation as how it’s being viewed?
I mean it seems to me that since we are increasing the view from 1 to 2 we are only enhancing how it’s being viewed (it should not affect the physical properties). Am I wrong?
If I’m correct, then again I see no enhancement in visual when this step is taken. Can someone clarify this?

How the eye lays in the socket is kind of a precise thing, notice the change in scale from a level one to a level two. You want it to be similar to the render options so there isn’t any weirdness happening when you hit F12.

Edit: view and render subdivision levels can be controlled separately for convenience; high levels in view can slow down workflow navigation, yet you want smooth meshes in the final render.